Chapter 11-BOILER FITTINGS AND CONTROLS 



SIDE VIEW 



END VIEW 



1. DESUPERHEATER INLET 



2. NOZZLE PLATES OF MANIFOLD 

 BAFFLE 



3. REMOVABLE APRON PLATES 

 OF MANIFOLD BAFFLE 



4. CYCLONE SEPARATORS 



5 DESUPERHEATER TUBES 



6 INTERNAL FEED PIPE 



7 FEED NOZZLE 



8 STEAM SCRUBBER SUPPORT 



9 MAIN STEAM CONNECTION 



10 DRY PIPE 



11 STEAM SCRUBBERS 



12 SURFACE BLOW LINE 



38.47X 



Figure 11-6.— Arrangement of internal fittings in older 

 single-furnace boiler. 



and water enters the separator tiirough a tapered 

 inlet section on the side nearest the shell of the 

 steam drum and follows a curving path along the 

 curve of the separator. The steam leaves 

 through the outlet orifices at each side of the 

 separator. The water, being heavier, continues 

 along the curve of the separator and is dis- 

 charged through drain holes in the drain baffle. 

 The knife edge on the drain baffle is there to 

 minimize turbulence. A second drain baffle 

 curves down below the knife edge and drains off 

 any water that might pass over the knife edge. 



The steam discharged from the horizontal 

 separators is channeled directly to the chevron 

 dryers which are installed near the top of the 

 drum, as shown in figure 11-8. A number of 

 these chevron dryers are installed along the 

 length of the steam drum. From the dryers, 

 the steam enters the rectangular dry box which 

 is fitted against the top of the steam drum. 

 The dry box acts as a chamber for the collection 

 of dry steam. 



The chemical feed pipe shown in figure 6-8 

 is connected to a nozzle on the end of the drum. 

 The chemical feed pipe and nozzle are used to 

 inject chemicals for boiler water treatment while 

 the boiler is in operation; they are also used 

 to draw samples of boiler water for testing. 



EXTERNAL FITTINGS AND CONNECTIONS 



External fittings and connections commonly 

 used on naval boilers include drains and vents, 

 sampling connections, feed stop and check 

 valves, steam stop valves, safety valves, soot 

 blowers, blow valves, water gage glasses, re- 

 mote water level indicators, superheater steam 

 flow indicators, pressure and temperature 

 gages, superheater temperature alarms, smoke 

 indicators, oil drip detector periscopes, single- 

 element feed water regulators, and other devices 

 that are closely connected to the boiler but not 

 installed in the steam and water spaces. 



Any listing of boiler external fittings and 

 connections tends to sound like a catalog of mis- 

 cellaneous and unrelated hardware. Actually, 

 however, all of the external fittings and con- 

 nections serve purposes that are related to 

 boiler operation. Some of the fittings and con- 

 nections allow you to control the flow of feed 

 water and steam. Others serve as safety 

 devices. Still others allow you to perform opera- 

 tional procedures— removing soot from the fire- 

 sides, for example, or giving surface blows— 

 that are necessary for efficient functioning of the 

 boiler. The instruments attached to or installed 



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